{"id":36386,"date":"2026-05-23T05:17:23","date_gmt":"2026-05-23T05:17:23","guid":{"rendered":"https:\/\/dimud.com\/?p=36386"},"modified":"2026-05-23T09:12:05","modified_gmt":"2026-05-23T09:12:05","slug":"cnc-machining-tolerances-guide","status":"publish","type":"post","link":"https:\/\/dimud.com\/ru\/cnc-machining-tolerances-guide\/","title":{"rendered":"CNC Machining Tolerances: A Practical Guide for Engineers and Product Teams"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"36386\" class=\"elementor elementor-36386\" data-elementor-settings=\"{&quot;ha_cmc_init_switcher&quot;:&quot;no&quot;}\" data-elementor-post-type=\"post\">\n\t\t\t\t<div class=\"elementor-element elementor-element-1e0e89e e-flex e-con-boxed e-con e-parent\" data-id=\"1e0e89e\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-eff0ec3 elementor-widget elementor-widget-heading\" data-id=\"eff0ec3\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Why Tolerances Define Whether Your Part Succeeds or Fails<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d6096de elementor-widget elementor-widget-image\" data-id=\"d6096de\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"image.default\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img fetchpriority=\"high\" decoding=\"async\" width=\"1280\" height=\"720\" src=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cnc-part-tolerance-band-diagram.webp\" class=\"attachment-2048x2048 size-2048x2048 wp-image-36446\" alt=\"CNC part tolerance band diagram\" srcset=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cnc-part-tolerance-band-diagram.webp 1280w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cnc-part-tolerance-band-diagram-400x225.webp 400w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cnc-part-tolerance-band-diagram-768x432.webp 768w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cnc-part-tolerance-band-diagram-18x10.webp 18w\" sizes=\"(max-width: 1280px) 100vw, 1280px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1caf3ea elementor-widget elementor-widget-text-editor\" data-id=\"1caf3ea\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Every engineered component exists on paper as a perfect number \u2014 a shaft diameter of 12.000 mm, a housing depth of 8.500 mm. In the real world, those perfect numbers are never achievable. Every cutting tool flexes slightly under load, every workpiece expands a fraction as it heats up, and every fixture introduces its own microscopic positional variation. The gap between the ideal dimension and what the machine actually produces is inevitable.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">What separates a well-engineered part from one destined for the scrap bin is not the elimination of this variation \u2014 it is the intelligent management of it. That management happens through CNC machining tolerances: the defined boundaries within which a dimension must fall for a part to be considered acceptable.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Getting tolerances right has a direct impact on assembly success, functional reliability, production cost, and lead time. Call them too tight without engineering justification, and you escalate costs, slow throughput, and put strain on supplier relationships. Leave them too loose, and parts won&#8217;t assemble cleanly, wear faster, or fail under load. This guide explains how tolerances work, what achievable precision looks like across different machining processes, and how to make decisions that align your design requirements with practical manufacturing realities.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-3b55b30 e-flex e-con-boxed e-con e-parent\" data-id=\"3b55b30\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-1694dee elementor-widget elementor-widget-heading\" data-id=\"1694dee\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">What CNC Machining Tolerances Actually Mean<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-0880cd8 elementor-widget elementor-widget-text-editor\" data-id=\"0880cd8\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">A tolerance is the total permissible variation in a dimension. For a nominal (target) size of 25.00 mm with a tolerance of \u00b10.05 mm, the acceptable range runs from 24.95 mm to 25.05 mm. Any measured part dimension that falls within this band passes inspection. Anything outside it is rejected.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Several core terms appear consistently in tolerance specifications:<\/p><ul class=\"[li_&amp;]:mb-0 [li_&amp;]:mt-1 [li_&amp;]:gap-1 [&amp;:not(:last-child)_ul]:pb-1 [&amp;:not(:last-child)_ol]:pb-1 list-disc flex flex-col gap-1 pl-8 mb-3\"><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Nominal dimension:<\/strong> The intended target size stated on the drawing<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Upper limit:<\/strong> The maximum acceptable measurement<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Lower limit:<\/strong> The minimum acceptable measurement<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Tolerance band:<\/strong> The arithmetic difference between upper and lower limits<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Deviation:<\/strong> The difference between the actual measured size and the nominal dimension<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Datum:<\/strong> A reference point, line, or plane used as the origin for measurement<\/li><\/ul><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Three ways of expressing dimensional tolerances appear on engineering drawings:<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Bilateral tolerance<\/strong> \u2014 the variation is split symmetrically around the nominal: 25.00 \u00b10.05 mm. This is the most common format and gives the machinist equal room on both sides of the target.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Unilateral tolerance<\/strong> \u2014 all allowable variation sits on one side of the nominal. A pin might be specified as 12.00 +0.00 \/ \u22120.02 mm, meaning it can only be at or below the nominal, not above it. Useful when interference or clearance in one direction is structurally critical.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Limit dimensions<\/strong> \u2014 the drawing states only the upper and lower limits directly, for example 24.95 \/ 25.05 mm, leaving the machinist to meet any dimension within that range.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-9ede7d2 e-flex e-con-boxed e-con e-parent\" data-id=\"9ede7d2\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-d2c4cc9 elementor-widget elementor-widget-heading\" data-id=\"d2c4cc9\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">The Two Main Tolerance Families: Dimensional and Geometric<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e050e75 elementor-widget elementor-widget-image\" data-id=\"e050e75\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"image.default\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" width=\"1280\" height=\"720\" src=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/gd-t-drawing-symbols-chart.webp\" class=\"attachment-2048x2048 size-2048x2048 wp-image-36445\" alt=\"GD&amp;T drawing symbols chart\" srcset=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/gd-t-drawing-symbols-chart.webp 1280w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/gd-t-drawing-symbols-chart-400x225.webp 400w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/gd-t-drawing-symbols-chart-768x432.webp 768w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/gd-t-drawing-symbols-chart-18x10.webp 18w\" sizes=\"(max-width: 1280px) 100vw, 1280px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-78cdaa9 elementor-widget elementor-widget-text-editor\" data-id=\"78cdaa9\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<h3 class=\"text-text-100 mt-2 -mb-1 text-base font-bold\">Dimensional Tolerances<\/h3><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Dimensional tolerances govern the size of features: lengths, diameters, depths, widths, and thread dimensions. They are the starting point for most drawings and the first tolerances a machinist consults.<\/p><h3 class=\"text-text-100 mt-2 -mb-1 text-base font-bold\">Geometric Dimensioning and Tolerancing (GD&amp;T)<\/h3><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Size alone is often insufficient to fully describe how a part must perform. A shaft might have a diameter within tolerance but still be bent. A flat surface might be the right height but badly warped. GD&amp;T addresses this by adding control over form, orientation, location, and runout through a standardized symbol language.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Common GD&amp;T controls include:<\/p><ul class=\"[li_&amp;]:mb-0 [li_&amp;]:mt-1 [li_&amp;]:gap-1 [&amp;:not(:last-child)_ul]:pb-1 [&amp;:not(:last-child)_ol]:pb-1 list-disc flex flex-col gap-1 pl-8 mb-3\"><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Flatness:<\/strong> How much a surface may deviate from a perfect plane<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Circularity (roundness):<\/strong> How closely a cross-section approaches a perfect circle<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Cylindricity:<\/strong> Combined control of diameter and straightness across a cylinder&#8217;s full length<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Perpendicularity:<\/strong> How precisely a feature sits at 90\u00b0 to a reference datum<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>True position:<\/strong> The allowed deviation from where a feature&#8217;s center must ideally be located<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Runout and total runout:<\/strong> How much a surface deviates as the part rotates around a datum axis \u2014 critical for rotating components such as shafts and bearing seats<\/li><\/ul><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">GD&amp;T is especially important in assemblies where multiple parts must align. Our <a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/services\/cnc-machining-services\/\">CNC machining services<\/a> team reviews GD&amp;T callouts as part of the drawing review process to flag any specifications that may create unnecessary cost or production risk before machining begins.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-30e4e2b e-flex e-con-boxed e-con e-parent\" data-id=\"30e4e2b\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-4b898cd elementor-widget elementor-widget-heading\" data-id=\"4b898cd\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Standard Tolerance Grades: ISO 2768 and IT Grades<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-99d7c1e elementor-widget elementor-widget-text-editor\" data-id=\"99d7c1e\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<h3 class=\"text-text-100 mt-2 -mb-1 text-base font-bold\">ISO 2768<\/h3><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><a href=\"https:\/\/www.iso.org\/standard\/7748.html\" rel=\"nofollow noopener\" target=\"_blank\">ISO 2768<\/a> is the most commonly referenced general tolerance standard for CNC machined parts. It defines default tolerance grades for linear dimensions, angular dimensions, and geometric characteristics when the drawing does not carry individual feature tolerances.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">The standard divides linear tolerances into four grades:<\/p><div class=\"overflow-x-auto w-full px-2 mb-6\"><table class=\"min-w-full border-collapse text-sm leading-[1.7] whitespace-normal\"><thead class=\"text-left\"><tr><th class=\"text-text-100 border-b-0.5 border-border-300\/60 py-2 pr-4 align-top font-bold\" scope=\"col\">Grade<\/th><th class=\"text-text-100 border-b-0.5 border-border-300\/60 py-2 pr-4 align-top font-bold\" scope=\"col\">Symbol<\/th><th class=\"text-text-100 border-b-0.5 border-border-300\/60 py-2 pr-4 align-top font-bold\" scope=\"col\">Application<\/th><\/tr><\/thead><tbody><tr><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">Fine<\/td><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">f<\/td><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">High-precision parts; tight-fit assemblies<\/td><\/tr><tr><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">Medium<\/td><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">m<\/td><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">General engineering; most machined components<\/td><\/tr><tr><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">Coarse<\/td><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">c<\/td><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">Fabricated structures; less critical dimensions<\/td><\/tr><tr><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">Very Coarse<\/td><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">v<\/td><td class=\"border-b-0.5 border-border-300\/30 py-2 pr-4 align-top\">Heavy structural work; rough machining<\/td><\/tr><\/tbody><\/table><\/div><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Most machining shops, including Dimud, default to <strong>ISO 2768-m<\/strong> (medium) for metal parts and <strong>ISO 2768-c<\/strong> (coarse) for plastic components unless the drawing specifies otherwise. When tighter dimensional control is needed, individual feature tolerances are added directly to the drawing.<\/p><h3 class=\"text-text-100 mt-2 -mb-1 text-base font-bold\">ISO 286 IT Grades<\/h3><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">For shaft and bore fits \u2014 the precision pairing of cylindrical features \u2014 ISO 286 defines a system of tolerance grades called International Tolerance (IT) grades, ranging from IT01 (most precise) through IT18 (least precise).<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">In general machining practice, IT6 to IT8 covers precision fits such as those used in bearing journals and locating pins. IT9 to IT11 addresses standard clearance fits. IT12 to IT14 handles loose fits and general dimensions where assembly tolerance is generous.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-71baacd e-flex e-con-boxed e-con e-parent\" data-id=\"71baacd\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-9dee9cd elementor-widget elementor-widget-heading\" data-id=\"9dee9cd\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Achievable Tolerances by Machining Process<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1de87de elementor-widget elementor-widget-image\" data-id=\"1de87de\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"image.default\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" width=\"1280\" height=\"720\" src=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cnc-milling-turning-grinding-precision.webp\" class=\"attachment-2048x2048 size-2048x2048 wp-image-36447\" alt=\"CNC milling turning grinding precision\" srcset=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cnc-milling-turning-grinding-precision.webp 1280w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cnc-milling-turning-grinding-precision-400x225.webp 400w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cnc-milling-turning-grinding-precision-768x432.webp 768w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cnc-milling-turning-grinding-precision-18x10.webp 18w\" sizes=\"(max-width: 1280px) 100vw, 1280px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-903db42 elementor-widget elementor-widget-text-editor\" data-id=\"903db42\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Different machining operations inherently achieve different precision levels. Choosing the right process for the required tolerance is a fundamental part of cost-effective part design.<\/p><h3 class=\"text-text-100 mt-2 -mb-1 text-base font-bold\">CNC Milling Tolerances<\/h3><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/services\/cnc-machining-services\/cnc-milling\/\">CNC milling<\/a> removes material with rotating multi-point cutters across three or more axes. Dimensional tolerances achievable with modern 3-axis and 5-axis milling centers typically range as follows:<\/p><ul class=\"[li_&amp;]:mb-0 [li_&amp;]:mt-1 [li_&amp;]:gap-1 [&amp;:not(:last-child)_ul]:pb-1 [&amp;:not(:last-child)_ol]:pb-1 list-disc flex flex-col gap-1 pl-8 mb-3\"><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Standard tolerance:<\/strong> \u00b10.1 mm \u2014 suitable for non-critical features, clearance fits, and cosmetic surfaces<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Medium precision:<\/strong> \u00b10.05 mm \u2014 the practical default for most structural and functional parts<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>High precision:<\/strong> \u00b10.01 mm \u2014 requires controlled environment, rigid fixturing, and sharp tooling<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Near-precision:<\/strong> \u00b10.005 mm \u2014 achievable on specific features with careful process setup<\/li><\/ul><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Surface finish from milling typically falls between Ra 0.8 \u03bcm and Ra 3.2 \u03bcm depending on toolpath strategy and cutter geometry.<\/p><h3 class=\"text-text-100 mt-2 -mb-1 text-base font-bold\">CNC Turning Tolerances<\/h3><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/services\/cnc-machining-services\/cnc-turning\/\">CNC turning<\/a> rotates the workpiece against a stationary cutting tool, producing cylindrical features with exceptional diameter consistency. For rotational parts, turning consistently outperforms milling in diameter control:<\/p><ul class=\"[li_&amp;]:mb-0 [li_&amp;]:mt-1 [li_&amp;]:gap-1 [&amp;:not(:last-child)_ul]:pb-1 [&amp;:not(:last-child)_ol]:pb-1 list-disc flex flex-col gap-1 pl-8 mb-3\"><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Standard:<\/strong> \u00b10.05 mm \u2014 adequate for shafts, bushings, and stepped cylinders used in general assemblies<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Precision:<\/strong> \u00b10.01 mm \u2014 appropriate for bearing journal fits and connectors requiring controlled clearance<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>High precision:<\/strong> \u00b10.005 mm \u2014 achievable on diameters requiring interference or precision transition fits<\/li><\/ul><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Live tooling on multi-axis turning centers allows secondary milled features to be added without re-fixturing, preserving the positional relationship between turned and milled features.<\/p><h3 class=\"text-text-100 mt-2 -mb-1 text-base font-bold\">CNC Grinding Tolerances<\/h3><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/services\/cnc-machining-services\/cnc-grinding\/\">CNC grinding<\/a> uses abrasive wheels operating at high speed to remove minimal amounts of material with exceptional surface integrity. It is the process of choice when dimensional precision must reach the extreme end of what CNC machining can achieve:<\/p><ul class=\"[li_&amp;]:mb-0 [li_&amp;]:mt-1 [li_&amp;]:gap-1 [&amp;:not(:last-child)_ul]:pb-1 [&amp;:not(:last-child)_ol]:pb-1 list-disc flex flex-col gap-1 pl-8 mb-3\"><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Standard grinding:<\/strong> \u00b10.005 mm<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>High-precision grinding:<\/strong> \u00b10.002 mm<\/li><li class=\"font-claude-response-body whitespace-normal break-words pl-2\"><strong>Ultra-precision surface and cylindrical grinding:<\/strong> \u00b10.001 mm<\/li><\/ul><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Surface roughness from grinding can reach Ra 0.1 \u03bcm to Ra 0.4 \u03bcm \u2014 significantly finer than milling or turning. Components destined for grinding are typically rough-machined first, then heat-treated or hardened if required, and finish-ground to final dimension. Dimud&#8217;s CNC grinding capability supports precision mold inserts, bearing-class components, and high-tolerance functional parts in our <a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/services\/mold-making-service\/precision-mold-manufacturing\/\">precision mold manufacturing<\/a> workflow.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-fc0593c e-flex e-con-boxed e-con e-parent\" data-id=\"fc0593c\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-77bafa0 elementor-widget elementor-widget-heading\" data-id=\"77bafa0\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">How Material Choice Affects Achievable Tolerances<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-95cc883 elementor-widget elementor-widget-image\" data-id=\"95cc883\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"image.default\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1280\" height=\"720\" src=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/machining-material-tolerance-comparison.webp\" class=\"attachment-2048x2048 size-2048x2048 wp-image-36444\" alt=\"machining material tolerance comparison\" srcset=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/machining-material-tolerance-comparison.webp 1280w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/machining-material-tolerance-comparison-400x225.webp 400w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/machining-material-tolerance-comparison-768x432.webp 768w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/machining-material-tolerance-comparison-18x10.webp 18w\" sizes=\"(max-width: 1280px) 100vw, 1280px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-aa56389 elementor-widget elementor-widget-text-editor\" data-id=\"aa56389\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Material behavior during cutting fundamentally limits how tight a tolerance can be held without driving up cost. Some materials machine predictably and hold dimension well; others introduce variability that requires additional process steps to manage.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Aluminum alloys<\/strong> are among the easiest materials for tight-tolerance work. They cut cleanly, generate lower cutting forces, dissipate heat efficiently, and exhibit stable dimensions once machined. Aluminum parts can routinely achieve \u00b10.01 mm and, with care, \u00b10.005 mm on critical features.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Stainless steel<\/strong> work-hardens during machining, generating heat that accelerates tool wear and causes thermal expansion of the workpiece. Achieving \u00b10.01 mm on stainless is feasible but requires sharper tooling, slower feeds, and more frequent inspection.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Brass and copper<\/strong> machine very freely with excellent surface finish but can smear at cut edges rather than shearing cleanly, which can affect thread and bore surface quality. Tight tolerances on these materials are achievable with the right toolpath strategy.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Titanium<\/strong> combines high strength, low thermal conductivity, and chemical reactivity with cutting tools \u2014 a challenging combination. Holding \u00b10.02 mm on titanium parts requires careful tool selection, rigid fixturing, and controlled feed rates.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Engineering plastics<\/strong> (ABS, PC, POM, and nylon) present a different set of challenges. Internal stresses in stock material can relax during machining, causing warping. Plastics absorb moisture from the environment, causing dimensional change over time. For this reason, ISO 2768-c (coarse) is often the practical standard tolerance for plastic CNC parts, with tighter values reserved for features where function demands it.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-ee3d33f e-flex e-con-boxed e-con e-parent\" data-id=\"ee3d33f\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-19ed5e9 elementor-widget elementor-widget-heading\" data-id=\"19ed5e9\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">The Direct Relationship Between Tolerance and Cost<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8c2277f elementor-widget elementor-widget-text-editor\" data-id=\"8c2277f\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">One of the most consequential decisions a designer makes is which features actually need tight tolerances and which can be left to standard default values. The cost impact of unnecessary precision is substantial and often invisible until a quote comes back.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Here is why tighter tolerances drive cost:<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Slower cycle times.<\/strong> Holding \u00b10.005 mm requires reduced feed rates, lighter depth-of-cut passes, and more conservative machining parameters throughout. The same part that takes 20 minutes at \u00b10.1 mm may take 60 minutes at \u00b10.005 mm.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>More frequent inspection.<\/strong> Tight features require in-process measurement with CMM (coordinate measuring machine), air gauges, or precision bore gauges \u2014 all of which add time. Parts at standard tolerance may be sampled; ultra-precision parts are often 100% inspected.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Grinding as a secondary operation.<\/strong> When tolerances are beyond what milling or turning can reliably hold, grinding is added as a secondary process \u2014 adding equipment time, setup, and handling.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Specialized tooling and fixturing.<\/strong> Holding 0.005 mm requires rigid, thermally stable fixtures and precisely balanced cutting tools. These add setup cost, especially for low-volume work.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Higher scrap rate.<\/strong> Tighter tolerance bands statistically catch more non-conforming parts, increasing rework and scrap costs.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">A practical approach: apply tight tolerances only to features that are functionally critical \u2014 bearing bores, locating pins, mating faces, and thread-fit diameters. Leave every non-functional dimension at the standard ISO 2768-m default. Submitting your design for <a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/services\/dfm-design\/\">Design for Manufacturability (DFM) analysis<\/a> before production begins is one of the most effective ways to catch over-toleranced features early and reduce costs without compromising part performance.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-d29d23a e-flex e-con-boxed e-con e-parent\" data-id=\"d29d23a\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-b510d1d elementor-widget elementor-widget-heading\" data-id=\"b510d1d\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Industry-Specific Tolerance Requirements<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3ebb34b elementor-widget elementor-widget-image\" data-id=\"3ebb34b\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"image.default\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1280\" height=\"720\" src=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/precision-parts-industry-applications.webp\" class=\"attachment-2048x2048 size-2048x2048 wp-image-36443\" alt=\"precision parts industry applications\" srcset=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/precision-parts-industry-applications.webp 1280w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/precision-parts-industry-applications-400x225.webp 400w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/precision-parts-industry-applications-768x432.webp 768w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/precision-parts-industry-applications-18x10.webp 18w\" sizes=\"(max-width: 1280px) 100vw, 1280px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-02a5471 elementor-widget elementor-widget-text-editor\" data-id=\"02a5471\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<h3 class=\"text-text-100 mt-2 -mb-1 text-base font-bold\">Automotive Components<\/h3><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/industries\/automotive\/\">Automotive parts manufacturing<\/a> demands consistency above all else. Components like housings, brackets, and shaft interfaces typically require tolerances in the \u00b10.02 mm to \u00b10.05 mm range for functional fits, with some bearing-class features needing \u00b10.005 mm to \u00b10.01 mm. Geometric tolerances for flatness of mating surfaces and true position of mounting holes are equally important, as automotive assemblies involve numerous sub-assemblies that must align precisely.<\/p><h3 class=\"text-text-100 mt-2 -mb-1 text-base font-bold\">Medical Device Manufacturing<\/h3><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/industries\/medical\/\">Medical device manufacturing<\/a> operates under some of the most stringent dimensional and process requirements of any industry. Surgical instrument components, implantable device housings, and diagnostic equipment parts commonly require tolerances of \u00b10.005 mm to \u00b10.01 mm, combined with surface finish specifications as fine as Ra 0.2 \u03bcm to ensure biocompatibility and prevent bacterial adhesion. Full traceability of material, process, and inspection records is expected for any medical-grade component.<\/p><h3 class=\"text-text-100 mt-2 -mb-1 text-base font-bold\">Electronics and Semiconductor<\/h3><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">For <a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/industries\/electronics\/\">electronics and semiconductor applications<\/a>, tight-tolerance CNC-machined components appear in sensor housings, connector interfaces, heat sink structures, and IC package guides. Positional tolerances on connector pin holes and interface flanges often specify \u00b10.01 mm to \u00b10.02 mm, as misalignment at the PCB level creates assembly failures downstream in production. Flat surface tolerances on heat-dissipating components are also critical for thermal interface performance.<\/p><h3 class=\"text-text-100 mt-2 -mb-1 text-base font-bold\">Robotics and Energy Storage<\/h3><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Structural frames and joint interfaces in robotics require both tight dimensional tolerances and geometric controls \u2014 particularly perpendicularity and true position \u2014 to ensure smooth motion under load. Energy storage components like battery housing inserts demand consistent press-fit or clearance diameters to maintain reliable electrical and mechanical contact across production batches.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-bc42dd3 e-flex e-con-boxed e-con e-parent\" data-id=\"bc42dd3\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-a1812a7 elementor-widget elementor-widget-heading\" data-id=\"a1812a7\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">How to Specify Tolerances Correctly on Technical Drawings<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e2e253b elementor-widget elementor-widget-text-editor\" data-id=\"e2e253b\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Poor tolerance specification is one of the most common sources of manufacturing delays and cost overruns. The following practices produce cleaner, more manufacturable drawings:<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Use a title block tolerance.<\/strong> Every drawing should define a general tolerance \u2014 typically ISO 2768-m for metal parts \u2014 that applies to all dimensions without an individual callout. This avoids ambiguity and simplifies the drawing.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Only call out tolerances tighter than the default where the function genuinely demands it.<\/strong> If a feature does not participate in an assembly fit or a functional interface, the title block tolerance is sufficient.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Specify critical fits using ISO 286 shaft and hole designations.<\/strong> A hole specified as \u00d820H7 and its corresponding shaft as \u00d820g6 immediately communicates the intended fit class (clearance, transition, or interference) to any competent machinist without requiring an additional note.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Accompany tight geometric tolerances with a clearly defined datum structure.<\/strong> A flatness or position callout is only meaningful if the inspection datum \u2014 the reference from which the measurement is made \u2014 is unambiguously identified on the drawing.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Avoid stacking tight tolerances across multiple features in an assembly.<\/strong> <a href=\"https:\/\/www.sigmetrix.com\/blog\/what-is-tolerance-stack-up-why-is-it-important\" rel=\"nofollow noopener\" target=\"_blank\">Tolerance stack-up<\/a> occurs when the combined variation of several features in a chain produces an assembly that falls outside acceptable limits even though each individual part is in tolerance. Early-stage design review through <a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/services\/cnc-machining-services\/cnc-prototyping\/\">CNC prototyping<\/a> helps identify stack-up problems before they affect production parts.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-b9fad9a e-flex e-con-boxed e-con e-parent\" data-id=\"b9fad9a\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-ad5b833 elementor-widget elementor-widget-heading\" data-id=\"ad5b833\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Common Mistakes That Lead to Tolerance Problems in Production<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-38040da elementor-widget elementor-widget-text-editor\" data-id=\"38040da\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Even experienced engineering teams encounter tolerance-related issues in production. The most frequent ones include:<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Treating all features equally.<\/strong> Applying \u00b10.01 mm across an entire drawing when only two or three features actually need it inflates cost and extends lead time without engineering benefit.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Ignoring material behavior.<\/strong> Specifying the same tolerance for a POM plastic bushing and a stainless steel shaft without accounting for the different machinability and thermal expansion of each material leads to unpredictable fit conditions in service.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Omitting surface finish from critical features.<\/strong> A bore can be dimensionally in-tolerance but still fail functionally if its surface roughness is too high, causing accelerated wear or seal leakage. Tolerance and surface finish specifications work together.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Over-specifying angular tolerances.<\/strong> Angular features such as chamfers, taper angles, and mating flanges are often given tighter angular tolerances than their function requires, adding inspection complexity and cost.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-fbd4a85 e-flex e-con-boxed e-con e-parent\" data-id=\"fbd4a85\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-c8b30db elementor-widget elementor-widget-heading\" data-id=\"c8b30db\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">How Dimud Maintains Tolerance Compliance Across Production<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3005640 elementor-widget elementor-widget-image\" data-id=\"3005640\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"image.default\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1280\" height=\"720\" src=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cmm-inspection-quality-control-process.webp\" class=\"attachment-2048x2048 size-2048x2048 wp-image-36448\" alt=\"CMM inspection quality control process\" srcset=\"https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cmm-inspection-quality-control-process.webp 1280w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cmm-inspection-quality-control-process-400x225.webp 400w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cmm-inspection-quality-control-process-768x432.webp 768w, https:\/\/dimud.com\/wp-content\/uploads\/2026\/05\/cmm-inspection-quality-control-process-18x10.webp 18w\" sizes=\"(max-width: 1280px) 100vw, 1280px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-10fa83d elementor-widget elementor-widget-text-editor\" data-id=\"10fa83d\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">At Dimud, tolerance control is not a final inspection activity \u2014 it is embedded throughout the production workflow.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Pre-production drawing review<\/strong> identifies unclear specifications, over-tight tolerances relative to part geometry, and any GD&amp;T callouts that require special fixturing or process planning before a single part is cut.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>In-process dimensional verification<\/strong> uses calibrated measurement equipment \u2014 including CMM inspection for complex geometries and precision gauging for shaft and bore fits \u2014 to confirm that parts are running within the tolerance band before the full batch is completed.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>First article inspection (FAI)<\/strong> on new parts validates that the production process consistently delivers dimensions within the specified tolerance range before volume production is approved.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><strong>Traceability<\/strong> through our ISO-aligned quality system links material certificates, process records, and inspection data to each production lot. Our full approach to quality management and certifications is detailed on our <a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/quality-certifications\/\">quality and certifications page<\/a>.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">This structured approach to tolerance management means that the precision your drawing specifies is the precision your delivered parts reflect \u2014 not just on the first sample, but consistently across every batch.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-511782e e-flex e-con-boxed e-con e-parent\" data-id=\"511782e\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-8476c7b elementor-widget elementor-widget-heading\" data-id=\"8476c7b\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Frequently Asked Questions<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c403d6d elementor-widget elementor-widget-elementskit-accordion\" data-id=\"c403d6d\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"elementskit-accordion.default\">\n\t\t\t\t\t<div class=\"ekit-wid-con\" >\n        <div class=\"elementskit-accordion accoedion-primary\" id=\"accordion-6a122556c4e73\">\n\n            \n                <div class=\"elementskit-card active\">\n                    <div class=\"elementskit-card-header\" id=\"primaryHeading-0-c403d6d\">\n                        <a href=\"#collapse-d746e106a122556c4e73\" class=\"ekit-accordion--toggler elementskit-btn-link collapsed\" data-ekit-toggle=\"collapse\" data-target=\"#Collapse-d746e106a122556c4e73\" aria-expanded=\"true\" aria-controls=\"Collapse-d746e106a122556c4e73\">\n                            \n                            <span class=\"ekit-accordion-title\">What is the standard tolerance for CNC machined parts?<\/span>\n\n                            \n                                <div class=\"ekit_accordion_icon_group\">\n                                    <div class=\"ekit_accordion_normal_icon\">\n                                        <!-- Normal Icon -->\n\t\t\t\t\t\t\t\t\t\t<i class=\"icon icon-down-arrow1\"><\/i>                                    <\/div>\n\n                                    <div class=\"ekit_accordion_active_icon\">\n                                        <!-- Active Icon -->\n\t\t\t\t\t\t\t\t\t\t<i class=\"icon icon-up-arrow\"><\/i>                                    <\/div>\n                                <\/div>\n\n                            \n                                                    <\/a>\n                    <\/div>\n\n                    <div id=\"Collapse-d746e106a122556c4e73\" class=\" show collapse\" aria-labelledby=\"primaryHeading-0-c403d6d\" data-parent=\"#accordion-6a122556c4e73\">\n\n                        <div class=\"elementskit-card-body ekit-accordion--content\">\n                            <p><br \/>For metal parts without individual tolerance callouts, the default at Dimud follows ISO 2768-m (medium grade), which for features in the 30\u2013120 mm range corresponds to \u00b10.1 mm. More critical features are specified with tighter individual tolerances directly on the drawing.<\/p>                        <\/div>\n\n                    <\/div>\n\n                <\/div><!-- .elementskit-card END -->\n\n                \n                <div class=\"elementskit-card \">\n                    <div class=\"elementskit-card-header\" id=\"primaryHeading-1-c403d6d\">\n                        <a href=\"#collapse-d0a3c786a122556c4e73\" class=\"ekit-accordion--toggler elementskit-btn-link collapsed\" data-ekit-toggle=\"collapse\" data-target=\"#Collapse-d0a3c786a122556c4e73\" aria-expanded=\"false\" aria-controls=\"Collapse-d0a3c786a122556c4e73\">\n                            \n                            <span class=\"ekit-accordion-title\">What is the tightest tolerance achievable with CNC machining?<\/span>\n\n                            \n                                <div class=\"ekit_accordion_icon_group\">\n                                    <div class=\"ekit_accordion_normal_icon\">\n                                        <!-- Normal Icon -->\n\t\t\t\t\t\t\t\t\t\t<i class=\"icon icon-down-arrow1\"><\/i>                                    <\/div>\n\n                                    <div class=\"ekit_accordion_active_icon\">\n                                        <!-- Active Icon -->\n\t\t\t\t\t\t\t\t\t\t<i class=\"icon icon-up-arrow\"><\/i>                                    <\/div>\n                                <\/div>\n\n                            \n                                                    <\/a>\n                    <\/div>\n\n                    <div id=\"Collapse-d0a3c786a122556c4e73\" class=\" collapse\" aria-labelledby=\"primaryHeading-1-c403d6d\" data-parent=\"#accordion-6a122556c4e73\">\n\n                        <div class=\"elementskit-card-body ekit-accordion--content\">\n                            <p>Through CNC grinding in a thermally controlled environment, tolerances of \u00b10.001 mm to \u00b10.002 mm are achievable on specific features. Standard milling and turning operations reliably achieve \u00b10.01 mm to \u00b10.05 mm for most parts.<\/p>                        <\/div>\n\n                    <\/div>\n\n                <\/div><!-- .elementskit-card END -->\n\n                \n                <div class=\"elementskit-card \">\n                    <div class=\"elementskit-card-header\" id=\"primaryHeading-2-c403d6d\">\n                        <a href=\"#collapse-63dbdec6a122556c4e73\" class=\"ekit-accordion--toggler elementskit-btn-link collapsed\" data-ekit-toggle=\"collapse\" data-target=\"#Collapse-63dbdec6a122556c4e73\" aria-expanded=\"false\" aria-controls=\"Collapse-63dbdec6a122556c4e73\">\n                            \n                            <span class=\"ekit-accordion-title\">Does tighter tolerance always mean a better part?<\/span>\n\n                            \n                                <div class=\"ekit_accordion_icon_group\">\n                                    <div class=\"ekit_accordion_normal_icon\">\n                                        <!-- Normal Icon -->\n\t\t\t\t\t\t\t\t\t\t<i class=\"icon icon-down-arrow1\"><\/i>                                    <\/div>\n\n                                    <div class=\"ekit_accordion_active_icon\">\n                                        <!-- Active Icon -->\n\t\t\t\t\t\t\t\t\t\t<i class=\"icon icon-up-arrow\"><\/i>                                    <\/div>\n                                <\/div>\n\n                            \n                                                    <\/a>\n                    <\/div>\n\n                    <div id=\"Collapse-63dbdec6a122556c4e73\" class=\" collapse\" aria-labelledby=\"primaryHeading-2-c403d6d\" data-parent=\"#accordion-6a122556c4e73\">\n\n                        <div class=\"elementskit-card-body ekit-accordion--content\">\n                            <p>No. Tolerances should reflect functional requirements. An unnecessarily tight tolerance on a non-critical feature adds cost and lead time without improving part performance. The goal is to specify exactly the precision the function demands \u2014 no tighter, no looser.<\/p>                        <\/div>\n\n                    <\/div>\n\n                <\/div><!-- .elementskit-card END -->\n\n                \n                <div class=\"elementskit-card \">\n                    <div class=\"elementskit-card-header\" id=\"primaryHeading-3-c403d6d\">\n                        <a href=\"#collapse-d86d47b6a122556c4e73\" class=\"ekit-accordion--toggler elementskit-btn-link collapsed\" data-ekit-toggle=\"collapse\" data-target=\"#Collapse-d86d47b6a122556c4e73\" aria-expanded=\"false\" aria-controls=\"Collapse-d86d47b6a122556c4e73\">\n                            \n                            <span class=\"ekit-accordion-title\">How do CNC tolerances relate to surface finish?<\/span>\n\n                            \n                                <div class=\"ekit_accordion_icon_group\">\n                                    <div class=\"ekit_accordion_normal_icon\">\n                                        <!-- Normal Icon -->\n\t\t\t\t\t\t\t\t\t\t<i class=\"icon icon-down-arrow1\"><\/i>                                    <\/div>\n\n                                    <div class=\"ekit_accordion_active_icon\">\n                                        <!-- Active Icon -->\n\t\t\t\t\t\t\t\t\t\t<i class=\"icon icon-up-arrow\"><\/i>                                    <\/div>\n                                <\/div>\n\n                            \n                                                    <\/a>\n                    <\/div>\n\n                    <div id=\"Collapse-d86d47b6a122556c4e73\" class=\" collapse\" aria-labelledby=\"primaryHeading-3-c403d6d\" data-parent=\"#accordion-6a122556c4e73\">\n\n                        <div class=\"elementskit-card-body ekit-accordion--content\">\n                            <p>Tight dimensional tolerances and fine surface finishes are often specified together because both influence how parts interact in assemblies. However, they are independently controlled. A part can be dimensionally accurate with a rough surface finish or dimensionally within tolerance with a very fine finish. Both parameters should be explicitly specified on the drawing when they matter.<\/p>                        <\/div>\n\n                    <\/div>\n\n                <\/div><!-- .elementskit-card END -->\n\n                \n                <div class=\"elementskit-card \">\n                    <div class=\"elementskit-card-header\" id=\"primaryHeading-4-c403d6d\">\n                        <a href=\"#collapse-5a2e69c6a122556c4e73\" class=\"ekit-accordion--toggler elementskit-btn-link collapsed\" data-ekit-toggle=\"collapse\" data-target=\"#Collapse-5a2e69c6a122556c4e73\" aria-expanded=\"false\" aria-controls=\"Collapse-5a2e69c6a122556c4e73\">\n                            \n                            <span class=\"ekit-accordion-title\">What information should I send to get an accurate tolerance-based quote?<\/span>\n\n                            \n                                <div class=\"ekit_accordion_icon_group\">\n                                    <div class=\"ekit_accordion_normal_icon\">\n                                        <!-- Normal Icon -->\n\t\t\t\t\t\t\t\t\t\t<i class=\"icon icon-down-arrow1\"><\/i>                                    <\/div>\n\n                                    <div class=\"ekit_accordion_active_icon\">\n                                        <!-- Active Icon -->\n\t\t\t\t\t\t\t\t\t\t<i class=\"icon icon-up-arrow\"><\/i>                                    <\/div>\n                                <\/div>\n\n                            \n                                                    <\/a>\n                    <\/div>\n\n                    <div id=\"Collapse-5a2e69c6a122556c4e73\" class=\" collapse\" aria-labelledby=\"primaryHeading-4-c403d6d\" data-parent=\"#accordion-6a122556c4e73\">\n\n                        <div class=\"elementskit-card-body ekit-accordion--content\">\n                            <p>The most useful submission includes a STEP or IGES 3D model accompanied by a 2D drawing with all critical tolerances called out, datum references for any GD&amp;T controls, and material and surface finish specifications. The more complete the drawing, the faster and more accurate the quotation.<\/p>                        <\/div>\n\n                    <\/div>\n\n                <\/div><!-- .elementskit-card END -->\n\n                                                        <script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[{\"@type\":\"Question\",\"name\":\"What is the standard tolerance for CNC machined parts?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p><br \/>For metal parts without individual tolerance callouts, the default at Dimud follows ISO 2768-m (medium grade), which for features in the 30\u2013120 mm range corresponds to \u00b10.1 mm. More critical features are specified with tighter individual tolerances directly on the drawing.<\/p>\"}},{\"@type\":\"Question\",\"name\":\"What is the tightest tolerance achievable with CNC machining?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>Through CNC grinding in a thermally controlled environment, tolerances of \u00b10.001 mm to \u00b10.002 mm are achievable on specific features. Standard milling and turning operations reliably achieve \u00b10.01 mm to \u00b10.05 mm for most parts.<\/p>\"}},{\"@type\":\"Question\",\"name\":\"Does tighter tolerance always mean a better part?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"<p>No. Tolerances should reflect functional requirements. An unnecessarily tight tolerance on a non-critical feature adds cost and lead time without improving part performance. 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The more complete the drawing, the faster and more accurate the quotation.<\/p>\"}}]}<\/script>\n                                <\/div>\n    <\/div>\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-4da897e e-flex e-con-boxed e-con e-parent\" data-id=\"4da897e\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;_ha_eqh_enable&quot;:false,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-0e5c6c7 elementor-widget elementor-widget-heading\" data-id=\"0e5c6c7\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"heading.default\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Work With a Team That Understands Tolerance from Design to Delivery<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-15573aa elementor-widget elementor-widget-text-editor\" data-id=\"15573aa\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Tolerance management is where engineering intent meets manufacturing reality. At Dimud, our CNC machining team works with customers across the full tolerance spectrum \u2014 from standard general-engineering components to precision mold inserts requiring sub-10-micron dimensional control.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\">Whether your project is in the early design stage and needs DFM feedback on tolerance feasibility, or you have fully defined drawings ready for production, our engineering team is available to review your requirements, identify any specification risks, and provide a detailed quotation.<\/p><p class=\"font-claude-response-body break-words whitespace-normal leading-[1.7]\"><a class=\"underline underline underline-offset-2 decoration-1 decoration-current\/40 hover:decoration-current focus:decoration-current\" href=\"https:\/\/dimud.com\/contact-us\/\">Contact Dimud for a CNC machining quote<\/a> \u2014 upload your CAD files and drawings, and our team will respond with engineering feedback and pricing within 24 hours.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Why Tolerances Define Whether Your Part Succeeds or Fails Every engineered component exists on paper as a perfect number \u2014 a shaft diameter of 12.000 mm, a housing depth of 8.500 mm. In the real world, those perfect numbers are never achievable. Every cutting tool flexes slightly under load, every workpiece expands a fraction as [&hellip;]<\/p>\n","protected":false},"author":28,"featured_media":36445,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[115,97],"tags":[],"class_list":["post-36386","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","category-guide"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/dimud.com\/ru\/wp-json\/wp\/v2\/posts\/36386","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dimud.com\/ru\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dimud.com\/ru\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dimud.com\/ru\/wp-json\/wp\/v2\/users\/28"}],"replies":[{"embeddable":true,"href":"https:\/\/dimud.com\/ru\/wp-json\/wp\/v2\/comments?post=36386"}],"version-history":[{"count":10,"href":"https:\/\/dimud.com\/ru\/wp-json\/wp\/v2\/posts\/36386\/revisions"}],"predecessor-version":[{"id":36451,"href":"https:\/\/dimud.com\/ru\/wp-json\/wp\/v2\/posts\/36386\/revisions\/36451"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/dimud.com\/ru\/wp-json\/wp\/v2\/media\/36445"}],"wp:attachment":[{"href":"https:\/\/dimud.com\/ru\/wp-json\/wp\/v2\/media?parent=36386"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dimud.com\/ru\/wp-json\/wp\/v2\/categories?post=36386"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dimud.com\/ru\/wp-json\/wp\/v2\/tags?post=36386"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}